Local media reported that the man beat the women on the breasts with various objects, using vacuum pumps, clothespins, electricity, and even a mouth spreader.
They took place in the cellar which he had converted into a torture chamber.
When the women cried out in pain, he forced them to perform sex acts.
Urs W. was finally caught when firemen dealing with a flood realised that there was an illegal cannabis plantation in one of the rooms of the industrial property which Urs W. rented in the town of Hausen.
Police were alerted, and decided to carry out a full search of the property in which they discovered that sexual abuse was carried out in a converted storage cellar which had been turned into a torture dungeon after they found extensive video material of the shocking scenes.
An investigation later uncovered details of the victims who were assaulted between November 2010 and December 2013.
In the darkened dungeon the police discovered a bed, lights, a video camera and a television, according to prosecutor Elisabeth Strebel. They also found anaesthesia tablets and Viagra.
Local media have speculated that the location was chosen because it was hard to reach and behind an industrial complex.
A forensic psychiatric analysis gave a report which described Urs W. as exhibiting "behaviour indicative of sexual sadism and a significant risk of relapse."
According to the indictment, Urs W. had 48 files with child pornography and 15 with animal pornography on his computer. He also had footage downloaded from the internet depicting women who were tormented and humiliated.
Urs W. did not deny that he filmed various sex acts. According to him, the women knew what they were doing when they took his medication and had agreed to the sexual acts in advance.
He said: "I have paid for everything and got what I wanted.
"Without video we would not be here. Nothing would have happened to anyone. I had my fun, and the women their money."
